Sunday, April 3, 2011

Scientists develop genetically modified cows that produce 'human' breast milk

Babies could be fed on ‘human’ milk produced by cows in the wake of the latest developments in genetic modification.
Scientists have bred 300 cattle that have been given human genes to make their milk contain the same nutrients and fat content as breast milk.
They believe the product could offer mothers an alternative to conventional infant formula.
Field of scientific development: Could dairy cows in the UK be producing human milk in the future?
Field of scientific development: Could dairy cows in the UK be producing human milk in the future?
But the move was condemned last night by campaigners who questioned its safety.
Human milk differs from cows’ milk in several important ways. It contains high quantities of nutrients beneficial to a baby’s growth and immune system.
Cows’ milk is much harder for a baby to digest, has less fat and fewer carbohydrates and contains no antibodies that protect against disease.
Prof Ning Li, who led the  research at the China Agricultural University, said the milk they produce would be as safe as ordinary cows’ milk.
Mother knows best: Developers say the new milk could help mothers who cannot breastfeed their babies and do not want to use formula
Mother knows best: Developers say the new milk could help mothers who cannot breastfeed their babies and do not want to use formula
‘The milk tastes stronger than normal milk,’ he said. ‘Within ten years, people will be able to pick up these human-milk-like products at the supermarket.’
But Patti Rundall, of Baby Milk Action, said: ‘We need to have rules in place to safeguard human health.
‘There could be incredible risks with these products that we don’t know about. Cows’ milk is never going to be like breast milk. It’s never going to be a living product like breast milk.
‘Breast milk is species specific – there is no element of risk.’
Writing in the respected journal Public Library of Science One, Prof Li’s team said they used cloning technology to introduce human genes into the DNA of Holstein dairy cows.
One variety of the GM cows produced milk containing lysozyme – an antimicrobial protein found in breast milk that protects babies from infection. They also created cows that produced human lactoferrin, a protein which boosts the immune system.
A third human milk protein called alpha-lactalbumin was also expressed in the milk. Prof Li claims his team has boosted the milk’s fat content by a fifth and changed the levels of solids to make it close to the composition of human milk.
But campaigners said the creation of GM cattle was bad for animal welfare. In two experiments by the Chinese in which 42 GM calves were born, just 26 survived. Ten died soon after birth and six died within six months.
A spokesman for the Royal Society for the Protection of Animals said: ‘Offspring of cloned animals often suffer health and welfare problems, so this would be a grave concern. Why do we need this milk – what is it giving us that we haven’t already got?’

 
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Helen Wallace, of watchdog GeneWatch UK, said: ‘There is a question about whether milk from these cows is going to be safe for humans, and it is really hard to tell that unless you do large clinical trials.’
China’s rules on GM food are more relaxed than those in Europe. The GM milk would not be allowed on sale in Britain unless it was approved by the European Union and passed stringent safety tests.
Some British scientists said the research could be of huge benefit.
Prof Keith Campbell, a biologist at Nottingham University and a member of the team that cloned Dolly the sheep in 1996, said GM animals were not a threat to health unless scientists deliberately gave them a gene that made their milk toxic.
‘Genetically modified food, if done correctly, can provide huge benefit for consumers in terms of producing better products,’ he said.
The modified milk could help boost sales of dairy products in Asia, where more than nine in  ten people are lactose intolerant and cannot consume cows’ milk without suffering stomach upsets and cramps.
Prof Li’s team were  working with the Beijing GenProtein Biotechnology Compan

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